Interactive Ruby Shell
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1.2.4 / May 2, 2020
Interactive Ruby Shell (IRB or irb) is a REPL for programming in the object-oriented scripting language Ruby. The abbreviation irb is a portmanteau of the word "interactive" and the filename extension for Ruby files, ".rb".
The program is launched from a command line and allows the execution of Ruby commands with immediate response, experimenting in real-time. It features command history, line editing capabilities, and job control, and is able to communicate directly as a shell script over the Internet and interact with a live server. It was developed by Keiju Ishitsuka.
Syntax and use
irb [ options ] [ programfile ] [ argument... ]
irb(main):001:0> n = 5 => 5 irb(main):002:0> def fact(n) irb(main):003:1> if n <= 1 irb(main):004:2> 1 irb(main):005:2> else irb(main):006:2* n * fact(n - 1) irb(main):007:2> end irb(main):008:1> end => :fact irb(main):009:0> fact(n) => 120 irb(main):001:0> class Cat irb(main):002:1> def meow irb(main):003:2> puts 'Meow!' irb(main):004:2> end irb(main):005:1> end => :meow irb(main):006:0> Cat.new.meow Meow!
- "All versions of irb". RubyGems.org. Retrieved 2020-07-06.
- "Code and run Ruby online" A powerful interactive Ruby shell
- "Try Ruby" Online IRB
- "When Trouble Strikes" chapter from Programming Ruby
- "Interactive Ruby Shell" chapter from Programming Ruby